Impeller

ABSTRACT

A second stage impeller for a snow blower. The impeller parts are made of light gauge sheet metal. The impeller base rotor is stamped in a dome shape to increase its strength and has attached thereto sheet metal impeller flights, each of which comprises a paddle transverse to the path of impeller rotation and a bracing strut behind the paddle. The paddle desirably has a top portion curved forward in the direction of impeller rotation and a reenforcing rib embossed in the curved portion. The base rotor has an opening through which the impeller shaft hub extends. A sheet metal cap is superimposed over the base rotor and has a rim fastened to the face of the base rotor and has an apertured crown spaced from the base rotor and through which the shaft hub extends.

United States Patent [191 Enters [52] US. Cl. ..37/43 R, 37/43 E, 302/38,

416/236 A [51] Int. Cl. ..E0lh 5/00 [58] Field of Search ..37/43, 43 A43 K,

37/53, 20-27, 189; 29/l56.8 R, 156.8 B, 156.8 CF, 156.8 H; 416/193, 194, 195, 197, 202, 235, 236, 236 A; 302/37, 38

[ 1 1 References Cited UNITED STATES PATENTS 1,889,816 1211931 White ..301 3'7 X 3,490,685 1 1970 Ferri ..302 37 x 3,588,179 6/1971 Gifford... ..302/37 2,408,459 10/1946 Tuttle ..37/43 C 2,723,445 11/1955 Trautvetter..... 29/l56.8 H 3,484,962 12/1969 Klapprodt ..37/43 B 2,245,759 6/1941 Chrisman.... ..29/l56.8 R X 2,334,456 11/1943 Thorp ..29/l56.8 RX 2,899,129 8/1959 Schwaiger... 29/156.8 CF X 2,474,840 7/1949 Greer ..37/43 B 2,743,538 5/1956 Linzy ..37/43 B 1 June 5, 1973 4/1970 Jensen ..29/156.8 R X 3,507,581 2,375,981 5/1945 Ellis ..37/21 2,695,071 11/1954 l-Iupp ..37/43 B FOREIGN PATENTS OR APPLICATIONS [57] ABSTRACT A second stage impeller for a snow blower. The impeller parts are made of light gauge sheet metal. The impeller base rotor is stamped in a dome shape to increase its strength and has attached thereto sheet metal impeller flights, each of which comprises a paddle transverse to the path of impeller rotation and a bracing strut behind the paddle. The paddle desirably has a top portion curved forward in the direction of impeller rotation and a reenforcing rib embossed in the curved portion. The base rotor has an opening through which the impeller shaft hub extends. A sheet metal cap is superimposed over the base rotor and has a rim fastened to the face of the base rotor and has an apertured crown spaced from the base rotor and through which the shaft hub extends.

7 Claims, 5 DrawingFigures 1 IMPELLER BACKGROUND OF THE INVENTION Heretofore, second stage impellers for snow throwers have been made by welding relatively heavy metal parts together. These parts were typically fabricated by rolling the parts from ten gauge sheet metal having a thickness of 0.1345 inches.

SUMMARY OF THE INVENTION and comprise paddles which face the direction of impeller rotation and bracing struts behind the flights. The upper portions of the paddles are curved forwardly and are provided with a reenforcing rib embossed therein. In one embodiment the paddles and struts are stamped out of one piece bent at an-angle between the paddle and strut.

The impeller shaft hub passes through an opening in the base rotor and also through the apertured crown of a superimposed sheet metal dome-shaped cap which has a rim fastened to the base rotor. The apertured crown of the cap is spaced from the base rotor to provide a bracing bracket for the impeller shaft.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of an impeller embodying the DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structure. The scope of the invention is defined in the claims appended hereto.

FIG. 4 shows a snow thrower 9 for which the impeller is adapted. The snow thrower 9 has a ribbon flight auger housing 10 at the rear of which is mounted the second stage impeller housing 1 1. The second stage impeller 12 is mounted in housing 11, and receives snow advanced thereto by the ribbon flight auger 8.

In accordance with the present invention, the impeller 12 comprises a base rotor 13 stamped out .of light gauge sheet metal, preferably 14 gauge metal which is 0.0747 inches thick. The rotor comprises a rim 14, a dome-shaped face 15, the contour of which adds strength thereto, and an open back. The peak of the dome is flattened and is provided with a central opening '16 to receive a tubular hollow shaft or hub 17 by which the impeller is driven from a drive shaft (not shown). In the illustrated embodiment the dome shaped face 15 constitutes a frustum of a cone. However, other dome shapes, such as those generated by single curved, double curved and warped surfaces, the contour of which adds strength to the light gauge sheet metal, are also appropriate. The dome shape is a marked improvement on prior flat rotors which had to be made of heavier gauge metal. to achieve requisite strength.

A series of snow impelling flights 20 are mounted on the dome-shaped face 15 of the base rotor 13. Flights 20 are fabricated by stamping out of light gauge sheet metal, also preferably 14 gauge. Each flight 20 comprises a paddle 21 and a bracing strut 22. Strut 22 is behind paddle 21 with respect to the direction 31 of rotation of rotor 12 and is at an angle thereto to support the paddle 21 as it impels snow. Desirably, both the paddle 21 and strut 22 are formed out of the same piece of metal and are interconnected on bend 23.

The impeller flights 20 are confined to the peripheral zone of the base rotor 15. The flights do not extend inwardly to the center of the rotor, thus leaving the center zone of the base rotor, as defined by the cap 33, smooth and clear. Thus the impeller develops a better throwing action with reduced power consumption.

The bottom edges of the paddle 21 and strut 22 are provided with mounting lugs 24 which arereceived in complementary socket apertures 25 formed in the face 15 of the rotor 13. Welds 26 desirably anchor the flight lugs 24 to the rotor face 15. The: provision for interlocking the lugs and sockets insures consistency in the accurate alignment of the flights on the rotor and also facilitates the welding process, inasmuch as the joint can be welded from the underside of the rotor, free from interference caused by the projecting flights.

Near their tops, the paddles 21 are curved forwardly at 27. The curve is reenforced by a rib 30 embossed in the paddle and extending into the face of the paddle 21 and through the curved portion 27 thereof. The curve 27 is in the direction of rotation of the impeller, as indi cated by arrow 31 in FIG. 1.

The hollow shaft or hub 17 is welded at 32 to the aperture 16 in the rotor 13. It is braced to the rotor by a 14 gauge stamped sheet metal cap 33 which is also dome-shaped, as shown in FIG. 3. Cap 33 has a rim 34 and a flat crown 35 with an aperture 36 through which the hollow shaft 17 extends, as shown in FIG. 2. The rim 34 is located over a series of weld openings 37 in the face 15 of the rotor, thus to receive welds 38 by which the cap 33 is secured to the rotor 13.

In the illustrated embodiment dome-shaped cap 33 is conical, the cone angle for cap 33 being somewhat sharper than the cone angle for base rotor 13. Accordingly, the crown 35 of cap 33 is spaced materially from the rotor face 15, thus to provide a brace for the hollow shaft or hub 17 which is welded at 41 to the crown35.

The hollow shaft or hub 17 receives a drive shaft (not shown) from the gear case of the snow thrower engine and is also provided with a shaft extension 42 by which the ribbon auger 8 is driven.

The rim 14 of rotor 13 is desirably provided with outstruck wiper teeth 44 which rotate in proximity to the housing wall 11. As best shown in FIG. 5 the wiper teeth 44 are desirably bent out of the flange 13 at about a 30 angle to the edge 46 of flange 13. Thus, forward edge or face 45 of the tooth 44 is exposed at the same 30" angle. In one embodiment the projection of face 45 is in the range of 0.05-0.06 inches laterally from the side wall of flange 13. Two or more such wiper teeth may be provided, as illustrated inFIG. 1, and are positioned to rotate in the space or gap 47 between flange l3 and housing wall 11.

Snow tending to flow through the gap 47 into the space behind the impeller 12 will be intercepted and picked up by the inclined faces 45 of the wiper teeth 44 and thrown ahead of the impeller and into the zone where the snow will be impelled by flights 20 through the discharge chute 48 of the snow thrower. Accordingly, the angled wiper teeth tend to prevent the snow from flowing through gap 47 in the first instance. The arrangement is greatly to be preferred over prior devices which allow the snow to flow into the space behind the impeller, where it tends to freeze up. Such wipers as are provided in such prior devices are faced with the problem of removing frozen snow which encrusts the space behind the impeller. By contrast, the angled wipers of the present invention tend to prevent the snow from flowing through gap 57 in the first instance, thus greatly reducing the formation of such encrustations.

While all of the parts of the second stage impeller are stamped out of light gauge metal, the unique configuration of these parts provides ample strength to the parts. The over-all result is a sturdy, less expensive, easy to assemble, consistent, impeller construction which requires fewer parts than prior art impellers and is lighter in weight. The impeller'of the present invention also affords a better impelling action. The novel wiper teeth have an improved snow excluding action to prevent snow from flowing into the space behind the impeller.

I claim:

1. An impeller comprising a sheet metal base rotor having a dome-shaped face with a center zone and a peripheral zone and sheet metal impeller flights confined to said peripheral zone to leave said center zone clear of flights, said flights being attached to said face in the peripheral zone of the rotor, said impeller flights each comprising a paddle transverse to the path of impeller rotation and a bracing strut behind the paddle, both said paddle and strut standing upright from said base rotor and being formed out of a single piece of sheet metal with a bend therebetween which forms a flight corner near the edge of the base rotor.

2. The impeller of claim 1 in which the paddles and struts of said flights have bottom edges provided with mounting lugs, the dome-shaped face of the rotor having mounting apertures receivingsaid lugs to expose said lugs at the undersurface of the rotor.

3. The impeller of claim 1 in which the flight paddles have top portions curved forward in the direction of impeller rotation, and a reenforcing rib embossed in said curved portion.

4. The impeller of claim 1 in which the base rotor and flights comprise light gauge sheet metal pieces.

5. The impeller of claim 1 in which said base rotor has a rim with wiping teeth.

6. The impeller of claim 5 in which the teeth are angled with respect to the direction of rotor rotation.

7. The impeller of claim 1 in combination with an impeller shaft hub, said base rotor having an opening through its center zone through which the shaft hubis received, and a dome-shaped sheet metal cap having a rim fastened to the center zone of the base rotor and an apertured crown spaced from the base rotor and through which said shaft hub extends. 

1. An impeller comprising a sheet metal base rotor having a dome-shaped face with a center zone and a peripheral zone and sheet metal impeller flights confined to said peripheral zone to leave said center zone clear of flights, said flights being attached to said face in the peripheral zone of the rotor, said impeller flights each comprising a paddle transverse to the path of impeller rotation and a bracing strut behind the paddle, both said paddle and strut standing upright from said base rotor and being formed out of a single piece of sheet metal with a bend therebetween which forms a flight corner near the edge of the base rotor.
 2. The impeller of claim 1 in which the paddles and struts of said flights have bottom edges provided with mounting lugs, the dome-shaped face of the rotor having mounting apertures receiving said lugs to expose said lugs at the undersurface of the rotor.
 3. The impeller of claim 1 in which the flight paddles have top portions curved forward in the direction of impeller rotation, and a reenforcing rib embossed in said curved portion.
 4. The impeller of claim 1 in which the base rotor and flights comprise light gauge sheet metal pieces.
 5. The impeller of claim 1 in which said base rotor has a rim with wiping teeth.
 6. The impeller of claim 5 in which the teeth are angled with respect to the direction of rotor rotation.
 7. The impeller of claim 1 in combination with an impeller shaft hub, said base rotor having an opening through its center zone through which the shaft hub is received, and a dome-shaped sheet metal cap having a rim fastened to the center zone of the base rotor and an apertured crown spaced from the base rotor and through which said shaft hub extends. 